Jet nozzle for drill bit



Feb. 4, 1964 J. 5. soonwm 3,120,284

. JET NOZZLE FOR DRILL BIT Filed Aug. 17, 1959 20 JON/V S. CWOM/l/V g 50 4/ JNVENTOR. 42

27 BY 6 rfi prrae/vgys United States Patent ()flice 3,120,284 Patented Feb. 4, 1964 3,120,284 JET NOZZLE FOR DRILL BllT John S. Goodwin, Whittier, Califi, assignor to Globe Oil Tools Company, Los Nietos, Calif., a corporation of California Filed Aug. 17, 1959, Ser. No. 834,179 2 Claims. (Cl. 175-340) This invention relates to the well drilling art and is particularly directed to an improvement in bits of the jet type. More specifically, this invention is concerned with an improved jet nozzle for a drill bit, the nozzle having an insert piece contained within a threaded metal container.

Jet bits of the general type shown in the Payne Patent No. 2,855,182 have the disadvantage that the split retainer ring which holds the nozzle in place is not protected from the abrasive action of the high speed jet of mud fluid, and it has been found in actual practice that erosion and failure of the split retainer ring takes place, followed by displacement of the jet nozzle from the bit body. The resulting reduction in back pressure on the slush pumps at the surface is immediately apparent, and suspension of drilling operations is required. The drill pipe must be removed from the hole to locate the cause of the drop in pressure, and this is a time consuming operation,

It is the principal object of the present invention to provide a superior mounting for the jet nozzle of a drilling bit. Another object is to provide improved means for releasably holding the nozzle in position and wherein the retaining means is protected from abrasive action of the jet fluid stream. Other and more detailed objects and advantages will appear hereinafter.

In the drawings:

FIGURE 1 is a sectional view partly broken away showing a drill bit assembly provided with a jet nozzle.

FiGURE 2 is a sectional view taken substantially on the lines 22 as shown in FlGURE 1 illustrating the nozzle assembly comprising my invention.

FIGURE 3 is a bottom plan view of the assembly shown in FIGURE 2.

Referring to the drawings, the drill bit generally designated is provided with a body 11 having a tapered threaded pin 12 engaging corresponding threads in the lower end of a drill collar sub 13. The bit body 11 is provided with circumferentially spaced legs 14, each rotatably supporting a cutter 15. Jet nozzle assemblies generally designated 16 provided on the bit body 11 serve to direct high velocity jets of drilling fluid against the bottom of the hole 17. Drilling fluid is supplied to the bit 10 through the interior of the drill string, and passages 18 formed in the bit body 11 carry the drilling fluid to the jet nozzle assembly 16.

In accordance with my invention, the bit body 11 is provided with annular shoulders 19 encircling the downstream ends of passageways 18. Metal sleeves 20 are each provided with an abutment 21 engaging the shoulder 19 and each having a central opening 22 which forms a continuation of the body passageway 18. The upper end of the metal sleeve 21} is piloted within the bore 23 of the bit body 11. The metal sleeve 20 is joined to the bit body 11 by welding material 24.

The metal sleeve 26 has a downward facing shoulder 25 and counterbores 26 and 27. Axially extending internal threads 28 connect the counterbores 26 and 27.

A metal retainer 30 has an upstanding rim 31 which projects into the counterbore 26 and into metal-to-metal engagement with the shoulder 25 on the metal sleeve 20. External threads 38 on the retainer 30 engage the internal threads 28 on the metal ring 20. External cylindrical portions 39 and 40 on the metal retainer 30 engage within the counterbore 27 and are separated by a circumferential groove 41 in the retainer which receives the rubber 0 ring 42. The tapered discharge opening 43 in the retainer 30 flares in a downward direction. Diametrically placed slots 44 are provided in the lower end of the retainer 30 for engagement by a wrench-like tool, not shown.

The nozzle 50 may be formed of ceramic material and has an outer cylindrical surface 51 which is received within the cylindrical bore 52 of the retainer 30. The nozzle rests on the shoulder 53. A layer of cementing material 54 is positioned between the surfaces 51 and 52, and between the lower end of the nozzle and the shoulder 53. This cementing material prevents leakage between the nozzle and the retainer. The nozzle has a central passage 55 extending therethrough. The upper end of this passage is larger than the lower end; the upper end is slightly larger than the bore 22 which is aligned therewith, and the lower end is smaller than the aligned discharge opening 43 in the retainer 30.

The metal sleeve 20 is welded to the bit body 11 and forms an integral part thereof. The retainer 30 and nozzle 50 and seal ring 42 constitute a unitary assembly which is installed and removed as a unit with respect to the metal sleeve 20. After the nozzle 50 has been cemented to the retainer 39, the retainer 30 is threaded into the metal sleeve 20 until the upper end of the skirt 31 on the retainer 30 engages the sleeve shoulder 25 in metal-to-metal contact. This construction avoids placing any compressive load on the ceramic nozzle 50 by means of the threads 28, 38. The O ring 42 seals against the counterbore 27 to prevent leakage along the threads 28, 38, and furthermore the action of this 0 ring 42 in wedging into the lower outer portion of the groove 41 under hydraulic load develops a friction force tending to prevent unscrewing of the threads. Both the O ring 42 and the threads 28, 38 are protected by the thick metal retainer from attack by turbulence caused by the high velocity fluid passing by jet action through the nozzle 50. Accordingly, erosion of the threads does not occur, and the jet nozzle assembly 16 remains in place during the extremely severe service to which these parts are subjected during drilling at the bottom of a well bore.

A suitable wrench tool, (not shown) may be inserted into the discharge opening 43 and radial slots 44 for installing or removing the retainer and nozzle from the position within the metal sleeve 20.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details hereinabove set forth, but my application is of the full scope of the appended claims.

I claim:

1. In combination: a bit body having a fluid passage and having a member provided with a central opening communicating with the fluid passage, the member having a downward facing shoulder and having a coaxial cylindrical bore, said member also having axially extending internal threads positioned between said downward facing shoulder and said cylindrical bore, a unitary nozzle assembly removably positioned within said member, said assembly including a metal retainer having axially extending external threads engageable with said internal threads, said retainer having a peripheral groove, a fluid operated seal ring positioned in said groove and engageable with said cylindrical bore, the retainer having a bore terminating in an upward facing shoulder and having an outlet opening, a nozzle extending within said bore of the retainer and resting on the latter said shoulder and cemented to the retainer,-said nozzle having a central passage extending from said opening in said memher. to said discharge opening in said retainer, whereby said unitary assembly of retainer, seal ring and nozzle may be installed as a unit Within said member by relative turning movement of the threaded parts to bring said assembly into engagement with said downward facing shoulder.

2. The combination set forth in claim 1 wherein the retainer is provided with a skirt which engages said downward facing shoulder.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES 1 Another H. C. Smith First, November 1957, World Oil, p. 197. a 

1. IN COMBINATION: A BIT BODY HAVING A FLUID PASSAGE AND HAVING A MEMBER PROVIDED WITH A CENTRAL OPENING COMMUNICATING WITH THE FLUID PASSAGE, THE MEMBER HAVING A DOWNWARD FACING SHOULDER AND HAVING A COAXIAL CYLINDRICAL BORE, SAID MEMBER ALSO HAVING AXIALLY EXTENDING INTERNAL THREADS POSITIONED BETWEEN SAID DOWNWARD FACING SHOULDER AND SAID CYLINDRICAL BORE, A UNITARY NOZZLE ASSEMBLY REMOVABLY POSITIONED WITHIN SAID MEMBER, SAID ASSEMBLY INCLUDING A METAL RETAINER HAVING AXIALLY EXTENDING EXTERNAL THREADS ENGAGEABLE WITH SAID INTERNAL THREADS, SAID RETAINER HAVING A PERIPHERAL GROOVE, A FLUID OPERATED SEAL RING POSITIONED IN SAID GROOVE AND ENGAGEABLE WITH SAID CYLINDRICAL BORE, THE RETAINER HAVING A BORE TERMINATING IN AN UPWARD FACING SHOULDER AND HAVING AN OUTLET OPENING, A NOZZLE EXTENDING WITHIN SAID BORE OF THE RETAINER AND RESTING ON THE LATTER SAID SHOULDER AND CEMENTED TO THE RETAINER, SAID NOZZLE HAVING A CENTRAL PASSAGE EXTENDING FROM SAID OPENING IN SAID MEMBER TO SAID DISCHARGE OPENING IN SAID RETAINER, WHEREBY SAID UNITARY ASSEMBLY OF RETAINER, SEAL RING AND NOZZLE MAY BE INSTALLED AS A UNIT WITHIN SAID MEMBER BY RELATIVE TURNING MOVEMENT OF THE THREADED PARTS TO BRING SAID ASSEMBLY INTO ENGAGEMENT WITH SAID DOWNWARD FACING SHOULDER. 